When using serato you should be able to use 4 layers on each player. I tried it recently and it worked great. You just need to remember which layer you are using, it can get a little confusing in the heat of the battle or if you have had one too many (lol)!!! Also if you assign the second player to the USB2 setting for the other laptop then that should work, theoretically. I am not sure about how you do the headphone cues for each DJ.